The general goal of the proposed research is to use the bilingual as a vehicle to illuminate the basic cognitive processes that serve as the interface between memory and language. The specific goal is to examine the factors that modulate the competition that arises when the bilingual's two languages are active during language comprehension and production. How does a bilingual read and speak words in one language when words in the other language are available and active? The planned studies have three aims. One is to identify the conditions that give rise to cross-language competition. Each of the experiments involves the comprehension or production of words in Li, L2, or under mixed conditions in which the two languages are directly competing with one another. A second aim of the proposed experiments is to identify the factors that modulate lexical activation in each language. If a bilingual's two languages are always active to some degree, then it becomes critical to understand how the resulting competition is resolved to allow selection of a single word in the target language. A third goal is to understand more fully the component processes that are engaged in translation. The goal of the proposed research is to use a range of converging approaches to answer these questions and to obtain evidence that will eventually constrain a unified model of the bilingual lexicon.